It’s been barely a month since Apple ended its long-running China iPad trademark dispute with Proview, after paying $60 million to settle, but already the tech giant is facing its fourth fresh lawsuit in the country, this time over FaceTime.

Following Chinese legal claims in relation to Snow Leopard and two Siri cases (including a university in Taiwan), a Taiwanese man is claiming that Apple’s video calling service infringes on a patent he holds for “voice network personal digital assistant” technology, according to MIC Gadget.

The man, whose surname is Lee, is reportedly not seeking specific compensation yet, but he has taken his case to the Intermediate People’s Court in Zhenjiang and is asking Apple to cease the violation.

It’s said that Lee’s patent was first owned by a former employer, although it has since been transferred to him. His lawyer claims that he developed it to help reduce the need for the expensive overseas calls which he regularly incurred through work:

Lee is a technian of a Taiwanese tech company, he needed to travel aboard to various cities for work, therefore he always made international call to his company, parents and friends. Due to this reason, Lee was inspired and came up with an idea of implementing internet call feature on phones. Subsequently, he applied a patent for this idea in 2003.

Local media [Chinese] report that the court has contacted Apple over the suit, but is yet to receive a response. The trial is due to start this month so the company will need to give it some attention soon.

Apple’s most recent quarterly earnings figures revealed sales of $5.7 billion in China. Although the rate of growth slowed from the second quarter of 2012, the figure represented an impressive 47 percent year-on-year increase.